Not componets, same problem as your car, speakers mounted low in the doors. Installed Polk Audio DX6 in the doors and made these panels to help bring the sound up. It really helps
eah kick panels are pretty much out of the question for my car, i put my foot right where they would be, and i'd kick the crap out of them geting in and out. I just need to find a pair of tweeters for my car..
btw, im buying an RE8 tonight, so maybe i could use that in an install.. i was thinking a spare tire deal if i can find a way to mount my spare tire elsewhere (Actually hell, i could use my 13w1 in my spare tire place, but im still buying a re8 tonight ) http://www.diysubwoofers.org/projects/carsub4.jpg
If you haven't already bought it, I'd strongly recommend an Image Dynamics ID8 over the RE8 for the money. It's only slightly more expensive and is a much better subwoofer.
Those or the Dayton DC28F. If you want to put out more, the LPG 26na tweeters are $37 each and are very good tweeters. Only thing is you don't want to cross them over lower than around 3.5khz (LPGs, I mean).